Effects of Resveratrol-Loaded Cyclodextrin on the Quality Characteristics of Ram Spermatozoa Following Cryopreservation

This study investigated the effects of pure and methyl-β-cyclodextrin loaded forms of resveratrol (10 µg/mL, 20 µg/mL, and 40 µg/mL) on ram sperm functions post-thawing. Semen samples were pooled and divided into ten groups: Control, RES10, RES20, RES40, CD10, CD20, CD40, RLC10, RLC20, and RLC40. The groups were pre-diluted with media containing the group-specific chemicals, followed by 15 min of incubation, dilution, and freezing. To assess the effects of the chemicals, a post-thaw sperm quality assessment was conducted. Motility and other velocity parameters were evaluated using computer-assisted semen analysis. The functional integrity of spermatozoa membranes was assessed with the hypo-osmotic swelling test, and the capacitation status of spermatozoa was determined through fluorescent microscopic evaluation. Additionally, flow cytometry was used to evaluate mitochondrial activity, oxidative stress, and the integrity of the sperm membrane and acrosome. The results indicated that cyclodextrin adversely affected sperm functions following freezing-thawing, notably increasing the rate of spermatozoa exhibiting pre-capacitation and mitochondrial activity by approximately 34% and 16%, respectively (<i>p</i> < 0.05). It was found that 20 µg/mL resveratrol prevented pre-capacitation (<i>p</i> < 0.05). Both resveratrol and resveratrol-loaded cyclodextrin groups improved post-thaw sperm qualities overall, demonstrating their utility for freezing ram semen. However, higher concentrations of resveratrol were found to negatively impact sperm functions.